Millions of Chinese netizens were prevented from accessing huge swathes of the Internet Tuesday, with many rerouted to a website owned by a U.S. company with ties to a group outlawed in China.

The China Internet Network Information Center (CNNIC), a state-run department, blamed a "malfunction in root servers" that blocked access to top-level domain names in China such as .com and .net, according to a post on its Sina Weibo account, the Twitter-like micro-blogging service.

Security analysts quoted by the official Xinhua news agency said this could have been the result of a cyber attack by hackers -- though this has not been proved.

Dynamic Internet Technology (DIT) confirmed it owns the web address users were redirected to but denied any involvement. It said the company's IP address is already blocked in China so users would have been met by a blank web page.

DIT President Bill Xia told CNN Wednesday that the Internet outage was likely caused by China's own web censorship system, more widely known by its infamous "Great Firewall" moniker, which controls access to content on the Internet inside China deemed unsuitable.

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"Their DNS hijacking system is used to redirect visits to certain websites to the wrong IP address," he said. "But this time it was likely a temporary misconfiguration that affected all domain names."

According to its website, the U.S.-based company provides a range of services including anti-censorship solutions and has worked "to provide web access to forbidden sites for Internet users in China," with the Epoch Times, a newspaper run by the Falun Gong, listed among its clients.

The Falun Gong is a spiritual movement that has been banned in China since 1999, accused of "spreading fallacies, hoodwinking people, inciting and creating disturbances and jeopardizing social stability."